Composting, Yes or No?

Should you start a compost pile? Here are some quick thoughts on the subject…

Compost is black gold. Gardeners add it to their existing soil to turn it into rich, garden loam. However, since I advocate raised beds and new potting mix to start a garden, the old method of tilling up your poor soil and incorporating a lot of compost is no longer needed. The native soil often contains thousands of viable weed seeds so adding compost and fertilizer just makes them grow that much faster. You end up with a weed patch instead of a garden!

Instead I use compost during the summer as mulch only. I spread out a top layer of about two inches and leave it alone. The nutrients break down over time to feed the soil naturally, and the mulch serves to keep the soil moist. Let your worms eat the compost and do the tilling for you! So the amount of compost I need for my garden is not very great.

Don’t get me wrong, composting is a lot of fun. It’s very emotionally satisfying to take kitchen scraps and yard waste and turn it into gardening gold. The question is whether it’s right for your family and the situation in your garden. Do you have the time to take on an additional project? If so, read on.

To get you started, I need to explain that there are two kinds of compost piles – hot and cold. Hot composting is a pile that really starts cooking. The heat comes from the microbial action as the various materials decompose. The good news is that this heat (over 140°) kills off weed seeds and harmful bacteria and you will have usable material in three to eight weeks. The bad news is that the pile will need to be turned regularly in order to heat up. Also, the heat will kill some of the good bacteria along with the bad. If you don’t turn it often your pile won’t reach the proper temperature and there will be material at the edges that never gets cooked. You’ll need a pile measuring at least three feet in each direction to move things along at a good pace. With a small yard you may never accumulate the amount of material you need for a good pile. So hot composting may not be worth the work.

Cold composting is a lot easier to do, but it takes much more time – often up to a full year. You simply make a pile and keep adding to it whenever you have the material. It’s less work and you don’t end up killing as many good bacteria, but the big problem is that many of the weed seeds survive quite nicely. If you use grass clippings as a compost ingredient, realize that every weed seed landing in your yard gets sucked into your mower. If you have a weed-free garden and you add cold compost to it you might as well be planting weeds! But if you don’t put any material in your pile that has weeds, cold composting is a good way to go.

Another alternative is to use one of those composting systems in a box, tub or tumbler. They can produce good compost in two to three weeks using a small amount of material, and turning it is simple – you just roll the box or turn a handle. But the cost of these systems, sometimes over $200, makes me think twice.